Initial Effects of Pentobarbital Sodium on Water Diuresis in Dogs

Summary The intravenous injection of an anesthetic dose of pentobarbital sodium into 5 trained dogs showing a water diuresis produced a quick temporary inhibition of the diuresis in 14 of 20 experiments. The urinary rate recovered and approached the diuretic rate but a second and more prolonged inhibition of the diuresis occurred. The remaining 6 of the 20 experiments showed an immediate and prolonged inhibition of the diuresis. In 12 of the 20 experiments the urinary rate at the time the experiment was concluded was beginning to recover. The immediate temporary antidiuresis could be correlated in time of onset and duration, with a period of hypotension that followed each dose of anesthetic. The delayed prolonged antidiuresis was not correlated with hypotension and is believed to be due to increased liberation of antidiuretic hormone.